[metapost] [NTG-context] MetaPost transformation

[Albrecht Kauffmann]

Hello Troy,

if you declare a transform variable (e.g., t), it works:

transform t;
t := identity rotated 270 yscaled 0.5;
show identity transformed t;
>> (0,0,0,1,-0.5,0)

Greetings
Albrecht

On Wed, 30 May 2012, Troy Henderson wrote:

> I've encountered a MetaPost issue, and since many MetaPost users also use
> ConTeXt (and vice-versa), I am posting this question on both lists.
>
> The command
>
>> show identity rotated 270 yscaled 0.5;
>
> outputs
>
> (0,0,0,1,-0.5,0)
>
> as expected, while the command
>
>> show identity transformed (0,0,0,1,-0.5,0);
>
> errors with
>
> ---
> ! Missing `)' has been inserted.
> <to be read again>
>                   ,
> l.26 ^^Ishow identity transformed (0,0,0,1,
>                                           -0.5,0);
> ---
>
> I am using MetaPost 1.504, and the problem seems to be that MetaPost does
> not like me using the sextuple (0,0,0,1,-0.5,0) directly, but this is the
> most convenient method for me to describe my transformations.  Is this a
> bug in MetaPost, or am I not allowed to use transformations directly with
> sextuples?
>
> Troy Henderson
>